The reason why it is hard to find people to clear Alexander 4 is due to random skill sets you have to work with in an anonymous environment.
I completed A4 on the first try. Why? because the tanks talked strategy BEFORE running into the fray. So the notion of a healer check instance is a slice of baloney. Also, healers should not be eating orbs, ads, or beams period. It becomes a healer check if the DPS in their glowing RAV gear don't know how to deal major damage. It also doesn't help if tanks with the tensile strength of a moist towelette go in there ill informed.
Tanks positioning between the legs and mitigating those annoying beams with stuns is a start. Healers should be opposite of each other at 4 o'clock and 8 o'clock positions. DPS should take care to stay away from them going into 3rd phase. Mark the add entrance points, stick to your quadrant to avoid splash on stack death. Also reference Mr. Happy's tutelage on the matter before EVERY new raid encounter.